Patent Document 1 and Patent Document 2 disclose focused ion beam (FIB) devices that have gas field ionization ion source (GFIS) and use gas ions such as hydrogen (H2), helium (He), and neon (Ne). Such gas focused ion beams (gas FIB) has an advantageous effect in that they do not bring Ga contamination to the specimen as in a gallium (Ga: metal) focused ion beam (Ga-FIB) from a liquid metal ion source (LMIS), which is used often nowadays.
In addition, the energy width of the gas ions extracted from GFIS is narrow and the size of an ion generation source is small in GFIS, and thus GFIS can form minute beams than Ga-FIB.
Such gas FIB devices are used as a scanning ion microscope having a high resolution. That is, an image of the specimen is formed by detecting secondary particles emitted from the specimen, synchronizing with the scanning the specimen with the ions.
Patent Document 3 discloses a pattern inspection device that use an ion beam, wherein the ion beam that has converged and scanned is neutralized and irradiates onto the specimen. The neutralization is performed by an electron emission source (grid etc. to which negative voltage is applied) which is provided to cross the ion beam.
Patent Document 4 discloses a surface analysis device that uses an ion beam, wherein the ion beam is charge-neutralized for irradiation of the specimen. The charge-neutralizing means is provided by exchanging charges in gas (and in a capillary). Here, in order to make energy of uncharged particle beams uniform and to remove particles other than uncharged particles, there are further provided a means for removing multivalent ions as pre-treatment and a means for removing charged particles as post-treatment.
Patent Document 5 discloses an analysis apparatus that uses ion beams of high energy (MeV level), wherein ion beams led from vacuum are applied to the specimen in atmospheric pressure such that the ion beams are transmitted through an exit window (pressure bulkhead). The pressure bulkhead is formed by attaching a gold thin film on a metal net-structured object. Here, since the net-structured object partially supports the pressure difference between inside and outside of the pressure bulkhead, the gold thin film through which the ion beams are transmitted can be made relatively thin. Thereby, analysis accuracy has improved. Patent Documents 6, 7 and 8 disclose techniques similar to those in Patent Document 5. Here, for example, methods for cooling the pressure bulkhead, methods for monitoring a beam amount, and methods for reinforcing the pressure bulkhead are disclosed.
Patent Document 9 describes an arrangement of a film that can transmit ion beams on an ion beam path in order to remove contamination of low energy that comes from, for example, inner walls, in an ion implantation device. The film is a high polymer thin film. Degradation is prevented by exchanging the film once in every fixed service period.